Aqueous dispersion, a coated subject and use of an aqueous dispersion

Abstract

There is disclosed an aqueous dispersion comprising a) inorganic particles b) at least one fatty acid or a salt thereof, c) a polymeric binder, and d) water, wherein said aqueous dispersion is free of organic solvent. There is also disclosed use of an aqueous dispersion comprising a) inorganic particles, b) at least one fatty acid or a salt thereof, c) a polymeric binder, and d) water, as a coating on a substrate surface, wherein said surface after coating displays an equilibrium contact angle higher than 120° degrees, preferably more than 135°, most preferably more than 150° for a drop of water on the surface. There is also disclosed a method for coating a substrate comprising contacting said substrate with the aqueous dispersion. The coating allows application in one step, it is non-toxic, safe for food packaging, and environmentally friendly as well as inexpensive.

1 . An aqueous dispersion comprising:
 a) inorganic particles comprising aragonite, wherein said inorganic particles have a D 50  of less than 20 μm,   b) at least one fatty acid or a salt thereof,   c) a polymeric binder, and   d) water.   
     
     
         2 . The aqueous dispersion according to  claim 1 , wherein said inorganic particles have an apparent density from about 0.30 g/ml to about 4 g/ml, and wherein said inorganic particles have a BET specific surface area from about 1 m 2 /g to about 20 m 2 /g. 
     
     
         3 . The aqueous dispersion according to  claim 1 , wherein said fatty acid or salt thereof has 8 to 22 carbon atoms. 
     
     
         4 . The aqueous dispersion according to  claim 1 , wherein said polymeric binder is selected from the group consisting of a carboxylated latex, a styrene-butadiene latex and a styrene acrylate. 
     
     
         5 . The aqueous dispersion according to  claim 1  further comprising at least one additive selected from the group consisting of an antioxidant, a biocide, a coalescence agent, a coloured inorganic particle, a crosslinker, a defoaming agent, a dye, a fungicide, a lubricant, an optical brightener, a rheology modifier, and any combination thereof. 
     
     
         6 . The aqueous dispersion according to  claim 1  further comprising a zirconium crosslinker. 
     
     
         7 . A subject at least partly coated by contacting said substrate with an aqueous dispersion according to  claim 1 , wherein said subject has an equilibrium contact angle higher than 120° degrees for a drop of water on the surface. 
     
     
         8 . Use of an aqueous dispersion comprising:
 a) acicular or scalenohedral inorganic particles   b) at least one fatty acid or a salt thereof,   c) a polymeric binder, and   d) water,   
       as a coating on a substrate surface, wherein said surface after coating displays an equilibrium contact angle higher than 120° degrees for a drop of water on the surface. 
     
     
         9 . Use according to  claim 8 , wherein said inorganic particles comprise at least one entity selected from ground calcium carbonate, and precipitated calcium carbonate. 
     
     
         10 . Use according to  claim 8 , wherein said inorganic particles comprise aragonite. 
     
     
         11 . Use according to  claim 8 , wherein said substrate is contacted with said aqueous dispersion and thereafter heated. 
     
     
         12 . A method for coating a substrate comprising contacting said substrate with an aqueous dispersion according to  claim 1 . 
     
     
         13 . The method according to  claim 12 , wherein said substrate further is heated after contacting said substrate with said aqueous dispersion. 
     
     
         14 . The method according to  claim 12 , wherein said method comprises at least one method step selected from the group consisting of spray coating, dip coating, roll application, free jet application, blade metering, rod metering, metered film press coating, air knife coating, curtain coating, flexography printing, roll coating, and powder coating. 
     
     
         15 . The subject of  claim 7 , wherein said subject has an equilibrium contact angle higher than 135° for a drop of water on the surface. 
     
     
         16 . The subject of  claim 15 , wherein said subject has an equilibrium contact angle higher than 150° for a drop of water on the surface. 
     
     
         17 . The use of  claim 8 , wherein said surface after coating displays an equilibrium contact angle higher 135° for a drop of water on the surface. 
     
     
         18 . The use of  claim 8 , wherein said surface after coating displays an equilibrium contact angle higher 150° for a drop of water on the surface.